Temperature-responsive stationary phase utilizing a polymer of proline derivative for hydrophobic interaction chromatography using an aqueous mobile phase

Hideko Kanazawa, Eri Ayano, Chikako Sakamoto, Reiko Yoda, Akihiko Kikuchi, Teruo Okano

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41 Citations (Scopus)


A new method of chromatography is proposed, utilizing a thermo-responsive polymer carrying an amino acid ester residue for the stationary phase of high-performance liquid chromatography (HPLC). We have been investigating the new concept of chromatography, a temperature-responsive chromatography, using temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm)-modified surface for HPLC with a constant aqueous media as the mobile phase. In this study, we designed and synthesized thermo-responsive poly(acryloyl-l-proline methyl ester) and its copolymer with N-isopropylacrylamide (NIPAAm). Homopolymers of acryloyl-l-proline methyl ester and copolymer were prepared by the reaction of radical telomerization. These polymers underwent a reversible phase transition from water-soluble forms into aggregates by changing the temperature, similar to PNIPAAm. The surface properties and functions of stationary phases modified with poly(acryloyl-l-proline methyl ester) were controlled by the external temperature. In the chromatographic system, we separated steroids and amino acids with a variety of hydrophobicities using a sole aqueous mobile phase. In contrast to a PNIPAAm-modified surface, a poly(acryloyl-l-proline methyl ester)-modified surface showed a greater affinity for hydrophobic amino acids.

Original languageEnglish
Pages (from-to)152-158
Number of pages7
JournalJournal of Chromatography A
Issue number1-2
Publication statusPublished - 2006 Feb 17



  • Amino acids
  • HPLC
  • Hydrophobic interaction chromatography
  • Poly(N-isopropylacrylamide)
  • Poly(acryloyl-l-proline methyl ester)
  • Separation
  • Steroids
  • Temperature-responsive polymer

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Organic Chemistry

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